Merge VideoDecodeAcceleratorImpl with VideoDecodeAccelerator

media/video/video_decode_accelerator.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
 #define MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 114 matching lines @@
   // "seek".
   virtual void Reset() = 0;
 
   // Destroys the decoder: all pending inputs are dropped immediately and the
   // component is freed.  This call may asynchornously free system resources,
   // but its client-visible effects are synchronous.  After this method returns
   // no more callbacks will be made on the client.  Deletes |this|
   // unconditionally, so make sure to drop all pointers to it!
   virtual void Destroy() = 0;
 
+  // GPU PROCESS ONLY.  Implementations of this interface in the
+  // content/common/gpu/media should implement this, and implementations in
+  // other processes should not override the default implementation.
+  // Returns true if VDA::Decode and VDA::Client callbacks can run on the IO
+  // thread. Otherwise they will run on the GPU child thread. The purpose of
+  // running Decode on the IO thread is to reduce decode latency. Note Decode
+  // should return as soon as possible and not block on the IO thread. Also,
+  // PictureReady should be run on the child thread if a picture is delivered
+  // the first time so it can be cleared.
+  virtual bool CanDecodeOnIOThread();
+
  protected:
   // Do not delete directly; use Destroy() or own it with a scoped_ptr, which
   // will Destroy() it properly by default.
   virtual ~VideoDecodeAccelerator();
 };
 
 }  // namespace media
 
 namespace base {
 
 template <class T>
 struct DefaultDeleter;
 
 // Specialize DefaultDeleter so that scoped_ptr<VideoDecodeAccelerator> always
 // uses "Destroy()" instead of trying to use the destructor.
 template <>
 struct MEDIA_EXPORT DefaultDeleter<media::VideoDecodeAccelerator> {
  public:
   void operator()(void* video_decode_accelerator) const;
 };
 
 }  // namespace base
 
 #endif  // MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_